1. Field of the Invention
The present invention relates to a slide fastener, and more particularly to a separable slide fastener having a separable bottom end stop assembly.
2. Prior Art
U.S. Pat. No. 3,030,684, issued Apr. 24, 1962 to Jones et al., discloses a separable slide fastener having a separable bottom end stop assembly comprising a pin member on one stringer and a socket member on the other stringer, the pin and socket members being formed on the stringers by injection molding and being releasably interlockable with each other to couple the stringers at their bottom ends. For the reinforcement purposes, a bottom end portion of each stringer is sandwiched by a pair of reinforcing parts integrally formed with and projecting from one of the pin and socket members. However, because the reinforcing parts, which have a great stiffness, extend up to an outer margin of the stringer, a sewing needle is difficult to smoothly penetrate through the stringer at its bottom end portion during the slide fastener is being sewn to a garment. Further, with such prior separable slide fastener, smooth coupling and uncoupling operation of the pin and socket members is difficult to achieve.
A solution to the above problems is disclosed in U.S. Pat. No. 3,503,102, issued Mar. 31, 1970 to Inazawa. According to the U.S. Pat. No. 3,503,102 a bottom end portion of the individual stringer is reinforced by a pair of synthetic resin films attached thereto one on each side while no reinforcing wings or projections are formed on either the pin member or the socket member. Thus the stringers are sufficiently flexible even at their bottom end portions, making the slide fastener capable of being smoothly sewn to a garment. However, the stringer tapes are liable to excessively bend at portion adjacent the pin and socket members, and as a result, the portions would become crumpled or otherwise damaged before long. With the tape portions thus damaged, smooth and reliable coupling and uncoupling operation of the pin and socket member is difficult to achieve. Another disadvantage of this prior art separable slide fastener is that the connections of the pin and socket members with the stringer tapes are not sufficiently firm.